[PATCH v4 0/7] dts: ti: k3-j7: Reserve memory for LPM metadata

[Richard Genoud (TI)]

For TI Jacinto SoCs (J7200, J721S2, J784S4, J722S, J742S2) which support
low power modes, a chunk of memory is reserved for LPM metadata, needed
for saving ATF context and the certificate information of ATF and OPTEE
and the DM image. This LPM metadata area is firewalled to be accessed
only by TIFS.

At boot time, U-Boot R5 SPL copies the DM image into this memory region
so that it doesn't have to be reloaded from storage at resume, speeding
up the resume time.

U-Boot R5 SPL/TIFS use this area to save and restore:
- ATF context
- ATF certificate information
- OPTEE certificate information
- DM image

https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/pm/lpm.html#lpm-msg-lpm-save-addr

NB: Unlike for Sitara, this memory region is not part of the DM memory,
which is not retained across suspend, so the Sitara binding can't be
re-used here.

Patch 1 adds a new binding for this layout.
Patch 2 skips the firewalled lpm-metadata memory region
The other patches add the memory region for the TI Jacinto SoCs (J7200,
J721S2, J784S4, J722S, J742S2)

Changes since v3:
- rebase on v7.3-rc4
- skip mapping the firewalled lpm-metadata memory region
Link to v3: https://lore.kernel.org/lkml/20260703143717.177362-1-richard.genoud@bootlin.com/

Changes since v2:
- Split the DTS changes per ipc-firmware.dtsi
- Reference the LPM carveout through a phandle
- Add a dt-bindings patch documenting the "lpm-metadata" memory-region
  name for the Jacinto layout.
- Use the generic @memory node naming instead of @lpm-memory.
- Clarify how the DM image is handled
Link to v2: https://lore.kernel.org/lkml/20260427160326.370415-1-richard.genoud@bootlin.com/

Changes since v1:
- add specific lpm region for j742s2 and j784s4 instead of the common
  one since the addresses are not the same.
- add j721s2 lpm_memory_region
- change j722s addresse to prevent holes
Link to v1: https://lore.kernel.org/lkml/20260312113446.1857592-1-p-mantena@ti.com/

Richard Genoud (TI) (7):
  dt-bindings: remoteproc: k3-r5f: Add Jacinto LPM memory region
  remoteproc: k3: skip mapping firewalled lpm-metadata memory region
  arm64: dts: ti: k3-j7200-ti-ipc-firmware: Reserve memory for LPM
    metadata
  arm64: dts: ti: k3-j721s2-ti-ipc-firmware: Reserve memory for LPM
    metadata
  arm64: dts: ti: k3-j784s4-ti-ipc-firmware: Reserve memory for LPM
    metadata
  arm64: dts: ti: k3-j722s-ti-ipc-firmware: Reserve memory for LPM
    metadata
  arm64: dts: ti: k3-j742s2-ti-ipc-firmware: Reserve memory for LPM
    metadata

 .../bindings/remoteproc/ti,k3-r5f-rproc.yaml  | 18 ++++++++--
 .../boot/dts/ti/k3-j7200-ti-ipc-firmware.dtsi | 12 +++++--
 .../dts/ti/k3-j721s2-ti-ipc-firmware.dtsi     | 12 +++++--
 .../boot/dts/ti/k3-j722s-ti-ipc-firmware.dtsi | 12 +++++--
 arch/arm64/boot/dts/ti/k3-j742s2-evm.dts      |  2 ++
 .../dts/ti/k3-j742s2-ti-ipc-firmware.dtsi     | 24 +++++++++++++
 .../dts/ti/k3-j784s4-ti-ipc-firmware.dtsi     | 15 ++++++++
 drivers/remoteproc/ti_k3_common.c             | 36 +++++++++++++------
 8 files changed, 111 insertions(+), 20 deletions(-)
 create mode 100644 arch/arm64/boot/dts/ti/k3-j742s2-ti-ipc-firmware.dtsi


base-commit: 93f51579e7df248780214094418f205253383cc5